CN1601892B - Distortion-compensated amplifier using predistortion technique - Google Patents

Abstract

The invention provides an amplifier with a distortion compensation function in a pre-distortion mode, which compensates the distortion generated by the amplifier for amplifying input signals through the pre-distortion mode, and reduces the influence of the memory effect of the amplifier. The memory effect distortion component compensating unit compensates the distortion component caused by the memory effect of the amplifier by using the time difference of the result of multiplying the input signal by an even power. As an example, an even power multiplying unit for multiplying an input signal by an even power, an even power result delay unit for delaying a signal of an even power result, and a device for detecting a difference between a signal of an even power result and a delayed signal An even power multiplication result time difference detection unit, an input signal multiplication unit for multiplying a signal of the detection result by an input signal, a distortion compensation coefficient multiplication unit for multiplying a signal of the multiplication result by a distortion compensation coefficient, and a multiplication unit for multiplying the input signal by the multiplication The result of signal addition is the distortion compensation coefficient multiplication result of the addition unit.

Description

Amplifier with distortion compensation function in pre-distortion mode

technical field

The present invention relates to an amplifier having a function of performing distortion compensation through predistortion, and particularly relates to a technique for reducing the influence caused by memory effects. the

Background technique

For example, in a base station apparatus of a mobile communication system, a signal to be transmitted is amplified by an amplifier in an amplifying unit of a transmitter. In addition, since nonlinear distortion occurs in the amplifier depending on the level of the input signal or the like, the distortion is compensated by a predistortion method or the like. the

However, in the conventional predistortion method, there is a problem that although it is possible to compensate the distortion generated in the amplifier which does not consider the memory effect, it cannot compensate the influence caused by the memory effect. In addition, various studies have been made to solve this problem (for example, refer to Non-Patent Document 1), but they are still insufficient, and further development is desired. the

[Non-Patent Document 1] Kawaguchi, Akayan, "Adaptive pre-distortion distortion compensation for amplifiers affected by even-order distortion", Japanese Journal of Science and Technology, MW2002-208 (2003-03), p.63-66

Contents of the invention

As shown in the above-mentioned conventional examples, further development of a structure for compensating distortion occurring in amplifiers that take memory effects into account in conventional amplifiers with a distortion compensation function by a predistortion method is desired. the

The present invention has been made in view of such conventional circumstances, and an object of the present invention is to provide an amplifier with a predistortion system distortion compensation function capable of reducing the influence of the memory effect. the

In order to achieve the above object, the present invention provides a kind of amplifier, and this amplifier comprises the amplifying part that amplifies input signal and memory effect distortion component compensating unit, and this amplifier has pre-distortion mode distortion compensating function, it is characterized in that:

In order to provide an inverse characteristic for compensating the distortion produced by the memory effect, the above-mentioned memory effect distortion component compensation unit modulates the amplitude and phase of the data signal from the predistorter with the time difference of the result of multiplying the input signal by an even power, thereby Compensate for the distortion component caused by the memory effect of the amplifier,

The memory effect distortion component compensation unit includes an even power multiplication unit that multiplies the input signal by an even power, an even power multiplication result delay unit that delays the signal of the even power multiplication result of the even power multiplication unit, and detects the even power The even power multiplication result time difference detection unit of the difference between the signal of the even power multiplication result of the multiplication unit and the delay signal of the even power multiplication result delay unit makes the signal of the detection result of the even power multiplication result time difference detection unit and the input signal an input signal multiplication unit for multiplication, a distortion compensation coefficient multiplication unit for multiplying a signal of a multiplication result of the input signal multiplication unit with a distortion compensation coefficient for compensating distortion, a distortion compensation coefficient multiplication unit for multiplying an input signal with a signal of a multiplication result of the distortion compensation coefficient multiplication unit Addition of distortion compensation coefficient multiplication result addition unit. the

In addition, in the amplifier with the predistortion method distortion compensation function of the present invention, when compensating the distortion generated in the amplifier amplifying the input signal by the predistortion method, the following processing is performed. the

That is, the memory effect distortion component compensating unit compensates the distortion component caused by the memory effect of the amplifier by using the time difference of the result of multiplying the input signal by an even power. the

As an example of the structure, the following structure is adopted in the amplifier with the distortion compensation function of the predistortion system according to the present invention. the

That is, in the memory effect distortion component compensation unit, the even power multiplication unit multiplies the input signal by an even power, and the even power multiplication result delay unit delays the signal of the even power multiplication result of the even power multiplication unit, and the even power The multiplication result time difference detection unit detects the difference between the signal of the even power multiplication result of the even power multiplication unit and the delay signal of the even power multiplication result delay unit, and the input signal multiplication unit takes the detection result of the even power multiplication result time difference detection unit The signal is multiplied by the input signal, the distortion compensation coefficient multiplication unit multiplies the signal of the multiplication result of the input signal multiplication unit by the distortion compensation coefficient, and the distortion compensation coefficient multiplication result addition unit multiplies the input signal and the signal of the multiplication result of the distortion compensation coefficient multiplication unit add up. the

Therefore, for example, the influence of the distortion component due to the memory effect of the amplifier can be reduced with a simple structure. the

Here, as the input signal, various signals can also be used. the

In addition, various values can be used as the order of the even power (that is, "n" which is the nth power of an even number). In addition, as an even power, a plurality of orders such as "2 power, 4 power, 6 power" and the like may be used. the

In addition, various values may be used as the time difference obtained by multiplying the input signal by an even power. the

In addition, as the delay time of the signal resulting from the even power multiplication, various times can be used depending on, for example, the time difference required in the result of the even power multiplication. the

In addition, various values can also be used as the distortion compensation coefficient. the

In addition, as the degree (accuracy) of compensating the distortion component, various degrees can be used as long as it is practically effective. the

In the amplifier with pre-distortion method distortion compensation function of the present invention, as a structural example, as shown below, the nonlinear distortion component compensation unit is based on the AM (amplitude modulation)-AM characteristic and AM-PM (phase modulation) characteristic of the amplifier. The distortion component caused by the nonlinearity is compensated. the

That is, in the nonlinear distortion component compensation unit, the even power multiplication unit multiplies the input signal by an even power, and the even power multiplication result multiplication unit performs an even power multiplication on the signal of the even power multiplication result of the even power multiplication unit and the input signal The distortion compensation coefficient multiplication unit multiplies the signal of the multiplication result of the even power multiplication result multiplication unit with the distortion compensation coefficient, and the distortion compensation coefficient multiplication result addition unit adds the input signal to the signal of the multiplication result of the distortion compensation coefficient multiplication unit . the

Therefore, for example, the influence of distortion components due to the AM-AM characteristics and AM-PM characteristics of the amplifier can be reduced with a simple structure, and the influence of distortion components due to the memory effect of the amplifier can also be reduced. As a whole, high-precision distortion compensation. the

Here, various values can be used as the order of the even power (that is, "n" that is the nth power of an even number). In addition, as an even power, a plurality of orders may be used. the

In addition, various values can be used as the distortion compensation coefficient. the

Hereinafter, structural examples of the present invention are further shown. the

As a structural example, the memory effect distortion component compensation unit is composed of the following parts: an even power multiplication unit for an even power to the input signal; an even power multiplication that delays the signal of the even power multiplication result of the even power multiplication unit Result delay unit; the even power multiplication result time difference detection unit of the difference between the signal of the even power multiplication result of the even power multiplication unit and the delay signal of the even power multiplication result delay unit; storage is detected by the even power multiplication result time difference The even power multiplication result time difference control value corresponding to the corresponding relationship between the value detected by the unit and the control value is corresponding to the storage unit; based on the storage content of the storage unit corresponding to the even power multiplication result time difference control value, according to the time difference detection unit The control value corresponding to the detected value is an input signal change unit that changes the input signal. the

Here, the input signal changing unit is, for example, a multiplication unit that multiplies the input signal by a control value, or an input signal amplitude and phase changing unit that changes one or both of the amplitude and phase of the input signal based on the control value. the

As a configuration example, a control unit is provided to perform feedback processing or processing based on the level of an input signal for the distortion compensation processing of the nonlinear distortion component compensating unit and the distortion compensating process of the memory effect distortion component compensating unit. the

As a configuration example, after the parameters of the distortion compensation processing of the nonlinear distortion component compensating means are updated and converged, the parameters of the distortion compensating processing of the memory effect distortion component compensating means are updated and converged, and then the update is alternately and repeatedly performed A process of multiplying and converging parameters of the distortion compensation processing of the nonlinear distortion component compensation unit by an even power, and a process of updating and converging parameters of the distortion compensation processing of the memory effect distortion component compensation unit. the

Here, as parameters, for example, various parameters such as distortion compensation coefficients and corresponding contents for control stored in a table can be used. the

As a configuration example, the input signal is a complex signal. As a structural example, the distortion compensation coefficient is a complex signal. As a configuration example, a multiplication unit for multiplying complex signals is configured using a complex multiplier. the

As a configuration example, it is provided in a base station device of a mobile communication system such as a mobile phone system or a simple mobile phone system (PHS: Personal Handyphone System), and the input signal is a signal to be wirelessly transmitted to a mobile station device or the like. the

As described above, according to the amplifier with predistortion distortion compensation method of the present invention, when compensating the distortion generated in the amplifier for amplifying the input signal by the predistortion method, the result obtained by multiplying the input signal by an even power is used. The time difference compensates for the distortion component due to the memory effect of the amplifier. Therefore, for example, the influence of the distortion component due to the memory effect of the amplifier can be reduced with a simple structure, and high-precision distortion compensation can be realized. the

Description of drawings

FIG. 1 shows a structural example of an amplifier with a distortion compensation function of a predistortion method according to this embodiment. the

Fig. 2 shows a configuration example of a memory effect predistorter according to the first embodiment of the present invention. the

Fig. 3 shows a configuration example of a memory effect predistorter according to a second embodiment of the present invention. the

Fig. 4 shows a configuration example of a memory effect predistorter according to a third embodiment of the present invention. the

Fig. 5 shows a configuration example of a predistorter according to a fourth embodiment of the present invention. the

FIG. 6 shows an example of the update processing procedure of the distortion compensation coefficient according to the fifth embodiment of the present invention. the

FIG. 7 shows an example of a simulation result of distortion compensation in the sixth embodiment of the present invention. the

Fig. 8 shows a configuration example of an amplifier with a distortion compensation function by a predistortion method. the

FIG. 9 shows an example of a graph of a distortion compensation table in consideration of memory effects. the

FIG. 10 shows an example of a model of an amplification unit in consideration of memory effects. the

Detailed ways

Embodiments of the present invention will be described with reference to the drawings. the

In this embodiment, a case where the present invention is applied to an amplifier with a predistortion system distortion compensation function included in a base station apparatus of a mobile communication system is shown. In the amplifier with pre-distortion mode distortion compensation function of this embodiment, the amplifier amplifies the multiple carrier signals to be amplified, and compensates the distortion that occurs in the amplifier. At this time, for the memory effect of the amplifier Effects are also compensated. the

First, a structural example of an amplifier with a predistortion system distortion compensation function of this embodiment will be shown. the

As shown in Figure 1, the amplifier with the predistortion mode distortion compensation function of the present embodiment possesses: in order to provide the inverse characteristic (predistortion) of the non-linear distortion of compensation AM-AM characteristic and AM-PM characteristic, to the input of the amplifier A predistorter 1 that modulates the amplitude and phase of the signal; a memory effect predistorter that modulates the amplitude and phase of the output signal from the predistorter 1 in order to provide an inverse characteristic (predistortion) that compensates for the distortion produced by the memory effect 2; an amplifying unit 3 for amplifying a transmission signal as an object of distortion compensation; and a control unit 4 for adaptively controlling the predistorter 1 and the memory effect predistorter 2. the

The predistorter 1, for example, performs distortion compensation based on instantaneous electric power as in the past, and is included in the case of using electric power detection means, a look-up table (LUT: Look Up Table), and the like. The predistorter 1 is used to compensate the AM-AM characteristic and the AM-PM characteristic of the amplifier of the amplifying unit 3, and in this example, no compensation is performed for the memory effect. the

The memory effect predistorter 2 compensates the distortion produced by the memory effect of the amplifiers of the amplification unit 3 . In this embodiment, the memory effect predistorter 2 multiplies the input signal by an even power, and uses the difference signal between the even power signal and the signal delayed by the even power signal. the

Here, the distortion produced by the AM-AM characteristic or the AM-PM characteristic and the distortion produced by the memory effect are determined by the input signal of the amplifying unit 3, not by the input of the amplifier with the pre-distortion mode distortion compensation function of this embodiment determined by the signal. Therefore, the distortion generated in the amplifying unit 3 is determined by a signal including changes in amplitude and phase due to the inverse characteristics of the distortion provided by the predistorter 1 and the memory effect predistorter 2 . the

In addition, according to the research of the present inventors, the amplitude and phase changed in the predistorter 1 are larger than the amplitude and phase changed in the memory effect predistorter 2, so as in this embodiment, the predistorter The memory effect predistorter 2 is configured in the latter stage of the device 1, and good characteristics can be obtained. the

On the other hand, in the structure in which the predistorter 1 is arranged in the subsequent stage of the memory effect predistorter 2, for example, the memory effect predistorter 1 inputs the input signal of the amplifier with the distortion compensation function of the predistortion mode to the amplifier. The memory effect in unit 3 is compensated, but because the amplitude and phase changes in predistorter 1 are relatively large, it is considered that the influence of memory effect predicted by memory effect predistorter 2 and the influence of memory effect actually occurred difference becomes larger. the

The amplifying unit 3 is composed of a single or a plurality of amplifiers, and has non-linear characteristics and memory effect characteristics to be subjected to distortion compensation. Generally, when the predistorter is used to compensate the distortion below -50~-60dBc, it is affected by the memory effect. the

The control unit 4 sets a distortion compensation table and a distortion compensation coefficient of each predistorter 1, 2, and performs processing for adapting to changes in the environment and the like. the

Next, the principle used in the memory effect predistorter 2 of this embodiment will be described. the

In the present embodiment, the cause of the memory effect is the offset variation caused by the electric power generated by the parasitic inductance, so the influence of the memory effect is compensated as follows. the

That is, the electromotive force generated by the inductor, that is, the power supply voltage variation V(t) is expressed by Equation 1. Here, t represents time, L represents inductance [H: Henry], and i(t) represents current. the

In addition, the above-mentioned formula 1 expresses like formula 2 with Δt as the minute time. the

V(t)＝L·{di(t)/dt} 

··(Formula 1)

V(t)＝L·{i(t)-i(t-Δt)}/Δt

··(Formula 2)

In this embodiment, the distortion caused by the memory effect in the amplifier is approximated by the above formula 2, and the memory effect is compensated by pre-adding the signal -V(t) to eliminate the distortion in the input to the amplifier. In the hardware of this embodiment, it is preferable to treat Δt as T (=one clock of the minimum time unit), but it does not deviate from this embodiment as long as, for example, the range can be approximated by a difference. In addition, in this embodiment, only the difference is processed, and it is realized with a simple structure, that is, the above-mentioned formula 2 is regarded as formula 3 and used. the

V(t)＝L·{i(t)-i(t-T)} 

··(Formula 3)

Example 1

The memory effect predistorter 2 of the first embodiment of the present invention will be described. the

As shown in Figure 2, the memory effect predistorter 2 of the present embodiment has a quadratic detector 11, a delay circuit 12, a subtractor 13, two (complex number) multipliers 14, 15, and similarly, a quadratic A detector 16 , a delay circuit 17 , a subtractor 18 , two (complex number) multipliers 19 and 20 , and an adder 21 are also provided. the

An example of the operation of the memory effect predistorter 2 of this embodiment is shown. the

The input signal is the I, Q digital baseband signal of the complex number vector. In this example, the input signal is the output signal from the predistorter 1 . the

The quadratic detector 11 detects the quadratic value of the input signal of the predistorter, and usually calculates the value of (I ² +Q ² ). The delay circuit 12 delays the output (detection value) from the quadratic detector 11 by T [sec]. The subtracter 13 subtracts the output of the quadratic detector 11 that is the output of the delay circuit 12 before T [sec] from the output of the quadratic detector 11 . The output signal P2 from the subtractor 13 is represented by the quadratic variance of Equation 4, when the I and Q input signals are expressed as I(t) and Q(t).

P2＝|I(t) ² +Q(t) ² |

-|I(tT) ² +Q(tT) ² |

··(Formula 4)

In addition, although T is preferably 1 clock time, for example, if it is within a range that can be approximated by a difference, it does not deviate from this embodiment. This quadratic variance corresponds to a differential coefficient. the

The multiplier 14 multiplies the quadratic variance value from the subtracter 13 by the input signal. This output corresponds to a signal obtained by re-modulating the carrier signal, and becomes a tertiary component, which has a frequency component near the carrier frequency. The multiplier 15 multiplies the output from the multiplier 14 by the distortion compensation coefficient E2. the

The distortion compensation coefficient E2 is expressed as a complex vector (E2real+j·E2imag), and is set so that the control unit 4 can compensate the distortion. Here, j represents an imaginary part. In addition, E2real represents a real number component, and E2imag represents an imaginary number component of E2. the

The complex vector E2 is represented by Equation 5. Here, sqrt means square root. In addition, |Amp| is an amplitude component, which is proportional to the magnitude of L in Equation 3 above, and corresponds to, for example, a fixed gain that provides the amplitude of secondary distortion. In addition, Phase is a phase component, for example, a fixed phase shift in the input signal, and is set to cancel out as the inverse of the phase change φ generated by the fixed phase changer 91 in FIG. 10 , for example. the

E2＝|Amp|·exp(j·Phase)

|Amp|＝sqrt{(E2real) ² +(E2imag) ² }

Phase＝tan ^-1 {(E2imag)/(E2real)}

··(Formula 5)

In the above, the signal path of the quadratic detector 11 has been described, but the same process is performed also in the signal path of the quadratic detector 16 . the

That is, the quartic value of the input signal is detected in the quaternary detector 16, the quaternary value is delayed in the delay circuit 17, and the non-delayed quartic value and the delayed quaternary value are detected in the subtractor 18. In the multiplier 19, the difference is multiplied by the input signal, and in the multiplier 20, the multiplication result is multiplied by the distortion compensation coefficient E4. the

The third-order component of the multiplication result of the multiplier 15 and the fifth-order component of the multiplication result of the multiplier 20 are input to the adder 21 . the

The adder 21 adds the input signal and the output from the 3rd or 5th predistorter (multipliers 15, 20), and outputs the addition result. In this example, this output signal is output to the amplifying unit 3 . the

The output signal SPD2(t) from the memory effect predistorter 2 of this embodiment is represented by Equation 6. the

SPD2(t)＝S2(t)+Diff2(t) E2 S2(t)

+Diff4(t)·E4·S2(t)

Diffn(t)＝|S2(t)| ⁿ -|S2(tT)| ⁿ

(n=2, 4)

··(Formula 6)

Here, S2(t) represents the input signal of the memory effect predistorter 2 . When the output signal SPD2(t) shown in the above formula 6 is input to the amplifier of the amplifying unit 3, the influence of the memory effect generated in the amplifier is canceled, so the output signal from the amplifying unit 3 becomes free from the influence of the memory effect. The signal, ie the distortion caused by memory effects, is compensated. the

In addition, in this example, only the 3rd-order term of the signal path of the quadratic detector 11 and the 5th-order term of the signal path of the quadratic detector 16 are illustrated, but for example, the number of types of orders used is not specified. Especially limited, in addition, generally, for other odd-numbered times (7 times, 9 times, ...), by using the 2nd power detector 11 and the 4th power detector 16 as other even power ( 6th power, 8th power, ...) detectors can also be expanded. the

As mentioned above, in the amplifier with pre-distortion distortion compensation function in this example, it has: the function of performing even power on the complex input signal; the delay function of providing delay for the output signal of the function of the even power; find the above even power The addition (subtraction) function of the difference between the output signal of the power function and the output signal of the above-mentioned delay function; the multiplication function that multiplies the input signal and the output signal of the above-mentioned addition function; the output signal of the multiplication function and complex distortion compensation a complex multiplication function that multiplies coefficients; an addition function that adds an input signal to an output signal of the above-mentioned complex multiplication function. the

Therefore, if the memory effect predistorter 2 of this example is used, when the input signal is amplified by the amplifier, the influence of the distortion component produced by the memory effect occurring in the amplifier can be compensated, thus, the adjacent channel can be realized. The reduction of leakage power consumption and parasitics can increase electric power efficiency. In addition, for example, the circuit scale can be reduced. the

Example 2

The memory effect predistorter 2 according to the second embodiment of the present invention will be described. the

As shown in FIG. 3 , the memory effect predistorter 2 of this example includes a quadratic detector 31 , a delay circuit 32 , a subtractor 33 , a look-up table (LUT) 34 , and a (complex) multiplier 35 . Here, the operations of the quadratic detector 31, the delay circuit 32, and the subtractor 33 are the same as, for example, 11, 12, and 13 shown in FIG. 2 above. the

In the LUT 34 is stored a table for memory effect compensation that the control unit 4 automatically converges. The LUT 34 takes the output from the subtracter 33 as a table reference variable. the

Then, the complex vector for distortion compensation stored in the table 34 is multiplied by the input signal by the multiplier 35 , and the result of the multiplication is used as an output signal to the amplifying unit 3 . the

After the output signal from the memory effect predistorter 2 of this example is input into the amplifier of the amplifying unit 3, the output of the amplifier becomes a signal without the influence of the memory effect. In addition, since the input signal of the memory effect predistorter 2 of this example is the output signal from the predistorter 1, the output from the amplifier of the amplifying unit 3 becomes a signal without distortion. the

In addition, in this example, only the case of three times is exemplified, but as described in the above-mentioned first embodiment, it can also be extended to other odd-number times. the

As mentioned above, possess in the memory effect predistorter 2 of this example: carry out the function of even power to the complex number input signal; To carry out the delay function of delaying the output signal of the function of this even power; Find the above-mentioned even order The addition (subtraction) function of the difference between the output signal of the square function and the output signal of the above-mentioned delay function; the memory function of storing the comparison table of the control value for distortion compensation; the complex multiplication that multiplies the input signal and the output signal of the above-mentioned memory Function. Also in this embodiment, the same effects as in the case of the first embodiment described above can be obtained. the

Example 3

The memory effect predistorter 2 as the RF predistorter according to the third embodiment of the present invention will be described. the

As shown in Fig. 4 (a), the memory effect predistorter 2 of the present embodiment includes: a quadratic detector 41 composed of a quadratic circuit, a delay circuit 42 composed of a delay element, and hardware such as an operational amplifier. Subtractor 43 for A/D conversion, A/D (analog/digital) converter 49a for A/D conversion, look-up table (LUT) 44, 2 D/A (digital/analog) converters 45, 46, variable voltage attenuation Device 47, voltage variable phase shifter 48. Here, the operations of the quadratic detector 41, the delay circuit 42, the subtractor 43, and the LUT 44 are the same as, for example, the operations of 31, 32, 33, and 34 shown in FIG. 3 above. As another structural example, in the structure of Fig. 4(b), the A/D converter 49a shown in Fig. 4(a) is not provided, but the A/D converter is provided behind the quadratic detector 41 49b. In addition, the delay circuit 42 and the subtractor 43 are the same as the delay circuit 32 and the subtractor 33 shown in FIG. 3, and are constituted by digital circuits or digital signal processing. the

Each D/A converter 45, 46 converts the control value stored in the table 44 into a voltage control signal by D/A conversion. A control value for controlling the voltage variable attenuator 47 is input from the table 44 to one D/A converter 45, and a control value for controlling the voltage variable phase shifter 48 is input from the table 44 to the other D/A converter 46. control value. the

The voltage variable attenuator 47 and the voltage variable phase shifter 48 are controlled by output signals from the respective D/A converters 45, 46, and these two devices function as a complex multiplier (for example, the above-mentioned one shown in FIG. 3 complex multiplier 35). This is particularly effective when the interface of the amplifier with distortion compensation function to the outside is an RF signal. the

In addition, in this example, only the case of three times is exemplified, and as described in the above-mentioned first embodiment, it can also be extended to other odd-number times. the

As mentioned above, in the memory effect predistorter 2 of this example, possess: carry out the function of even power to the complex number input signal; To carry out the output signal of the function of this even power to provide the delay function of delay; Find above-mentioned even power The addition (subtraction) function of the difference between the output signal of the power function and the output signal of the above-mentioned delay function; the memory function of saving the comparison table of the control value for distortion compensation; the D/ A conversion function; an attenuator that makes the attenuation amount of the input signal variable according to the output signal of the above-mentioned D/A conversion function; a phase shifter that makes the phase shift amount of the input signal variable according to the output signal of the above-mentioned D/A converter device. Also in this embodiment, the same effects as in the case of the first embodiment described above can be obtained. the

Example 4

A predistorter 1 according to a fourth embodiment of the present invention will be described. the

An example of the configuration of the predistorter 1 is shown in FIG. 5( a ). the

The predistorter 1 of this example includes an envelope detection circuit 51 , a look-up table (LUT) 52 , and a (complex) multiplier 53 . the

The envelope detection circuit 51 detects the envelope voltage or electric power of the input signal, and the output (detection value) corresponds to the instantaneous electric power of the input signal. Taking this output as a reference variable, using the distortion compensation coefficient stored in the distortion compensation table 52, the complex multiplier 53 performs complex multiplication of the distortion compensation coefficient and the input signal, thereby providing the input signal with AM-AM characteristics or AM - Inverse characteristic of PM characteristic. The signal provided with this inverse characteristic is output to the memory effect predistorter 2 . the

Another configuration example of the predistorter 1 is shown in FIG. 5( b ), which is an example when performing pseudo predistortion. the

The predistorter 1 of this example includes an envelope detection circuit 61, an A/D converter 65 for A/D conversion, a lookup table (LUT) 62, and two D/A converters 66 and 67 for D/A conversion. , a voltage variable attenuator 63 , a voltage variable phase shifter 64 . The input signal is an RF signal. the

The envelope detection circuit 61 detects the envelope voltage or electric power of the input signal. The output (detection value) is A/D converted by the A/D converter 65, and the amplitude control value and the phase control value stored in the distortion compensation table 62 are output by the D/A converters 66 and 67 as reference variables, By controlling the voltage variable attenuator 63 and the voltage variable phase shifter 64 according to each control value, AM-AM characteristics or inverse characteristics of AM-PM characteristics are provided to the input signal. The signal provided with this inverse characteristic is output to the memory effect predistorter 2 . the

FIG. 5( c ) shows another configuration example of the predistorter 1 . the

The predistorter 1 of this example includes a quadratic detector 71 and two (complex) multipliers 72, 73, and similarly, a quadratic detector 74 and two (complex) multipliers 75, 76. In addition, An adder 77 is also provided. The input signal is a complex I, Q baseband digital signal. the

The square detector 71 calculates the square value of the input signal. The multiplier 72 multiplies the input signal by the quadratic value, and the output (multiplication result) has the input amplitude raised to the third power, and the phase remains unchanged. The multiplier 73 complex multiplies the output signal from the multiplier 72 by the distortion compensation coefficient O3. the

Likewise, the 4th power detector 74 calculates the 4th power value of the input signal. The multiplier 75 multiplies the input signal by the quadratic value, and the output (multiplication result) has the amplitude of the input raised to the fifth power, and the phase remains unchanged. The multiplier 76 complex multiplies the output signal from the multiplier 75 by the distortion compensation coefficient O5. the

In addition, the distortion compensation coefficient O3 is expressed as a complex vector (O3real+j·O3imag), and is set so that the control unit 4 can compensate for distortion. Here, O3real represents the real number component of O3, and O3imag represents the imaginary number component of O3. the

The complex vector O3 is represented by Equation 7. Here, |Amp| is the amplitude component, and Phase is the phase component. the

The same applies to the distortion compensation coefficient O5. the

O3＝|Amp|·exp(j·Phase)

|Amp|＝sqrt{(O3real) ² +(O3imag) ² }

Phase＝tan ^-1 {(O3imag)/(O3real)}

··(Formula 7)

The adder 77 adds the input signal, the complex multiplication result input from the multiplier 73 three times, and the complex multiplication result input five times from the multiplier 76, and inputs the addition result to the memory effect predistorter 2. In this way, the adder 77 adds odd-numbered (for example, 3, 5, 7, . . . ) signals to the input signal to provide AM-AM characteristics and inverse characteristics of AM-PM characteristics. the

The output signal SPD1(t) from the predistorter 1 of this example is represented by Equation 8. the

SPD1(t)＝S1(t)+O3·S1' ³ (t)+O5·S1' ⁵ (t)

S1' ⁿ (t)＝|S1(t)| ^n-1 ·S1(t)

(n=3, 5)

··(Formula 8)

Here, S1(t) is the input signal of the predistorter 1 of this example. In this example, since the coefficient of the fundamental wave is fixed to (1+j·0), the gain and phase of the input signal are kept constant in the predistorter 1 . the

In addition, after the predistortion component of the output signal from the predistorter 1 of this example is input to the amplifier of the amplifying unit 3, since it cancels out the influence of the AM-AM characteristic or the AM-PM characteristic occurring in the amplifier, therefore The output signal from the amplifying unit 3 becomes a signal without distortion, that is, the distortion is compensated. the

In addition, in this example, only cases of 3 and 5 times are exemplified, but as described in the above-mentioned first embodiment, it can also be expanded for other odd times. In a structure like this example, there is also the advantage of not having a memory (LUT). the

As mentioned above, in the predistorter 1 of this example, possess: the function of carrying out the even power to the complex input signal; The multiplication function of multiplying the input signal with the output signal of the above-mentioned even power function; Make the above-mentioned multiplication function a complex multiplication function for multiplying an output signal by a complex distortion compensation coefficient; an addition function for adding an input signal to an output signal of the complex multiplication function described above. the

Example 5

The convergence algorithm of the amplifier with the distortion compensation function of the predistortion method according to the fifth embodiment of the present invention will be described. the

In this example, as the predistorter 1 and the memory effect predistorter 2, devices of various structures can be used respectively. the

FIG. 6 shows an example of the processing flow of the convergence algorithm of this example. the

That is, after starting the updating process of the distortion compensation coefficients (step S1), first update the distortion compensation coefficients O3, O5, ... (or LUT) of the predistorter 1 (step S2), so that they converge to the most able to compensate the distortion Optimum value (step S3), then, update the distortion compensation coefficient E2, E4, ... (or LUT) of memory effect predistorter 2 (step S4), make it converge to the optimum value ( Step S5), then, after the convergence for the first time, the update of the distortion compensation coefficient is not ended, and the subsequent process is entered to alternately update the distortion compensation coefficient of the predistorter 1 and the memory effect predistorter 2 (step S6, step S5). S7), adapting to various changes caused by temperature or passing years. the

Here, in general, the distortion caused by the AM-AM characteristic and the AM-PM characteristic is greatly dominant compared with the distortion caused by the memory effect, so as in this example, when updating the distortion compensation coefficient of the predistorter 1 After making it converge, updating the distortion compensation coefficient of the memory effect predistorter 2 and making it converge can shorten the convergence time (that is, speed up the convergence) compared with the reverse processing sequence. the

As a method of converging, for example, as shown in Equation 5 or Equation 7 above, the complex coefficients may be divided into amplitude |Amp| and phase Phase and converged. In addition, as another method, complex numbers may be divided into real numbers and imaginary numbers and converged, or both variables may be converged. In addition, in the case of using LUT, for example, it is also possible to converge using representative points, or to use a method of collective generation such as a spline method. In addition, the distortion compensation coefficient of the predistorter 1 and the distortion compensation coefficient of the memory effect predistorter 2 can be converged together by using MMSE (Minimum Mean Square Error) or the like. the

In addition, in the control of updating the distortion compensation coefficient (or LUT) of the predistorter 1 and the memory effect predistorter 2, for example, a signal output from the amplifying section 3 can be used as a feedback signal. the

As an example, frequency conversion is performed by a mixer as a feedback signal, unnecessary waves such as a carrier wave are removed by a band-pass filter, and only distortion electric power is detected. In addition, the oscillator is controlled in order to evaluate the distortion electric power of different frequencies such as IMD3+ or IMD3- by a DSP (Digital Signal Processor). In the algorithm, for example, perturbation method, update coefficient, etc. are used to reduce the detected distortion electric power. This algorithm has the advantage that it can be implemented simply and inexpensively. As another example, a method of demodulating a distorted signal and extracting an error with the input signal may be used, but such a method requires high speed and tends to be expensive. the

In the algorithm, for example, first, only the three times of gain of the predistorter 1 are updated by the given number of times, and then the three times of phase are updated. This process is performed in the order required 5 times, 7 times, . . . Then, if all the coefficients of the predistorter 1 converge, the coefficients of the memory effect predistorter 2 are also updated. Then, even if all the coefficients are converged, the DSP etc. will continue to update and adaptively follow the environment that changes due to temperature or aging. the

As described above, in the amplifier with the predistorter system distortion compensation function of this example, as an adaptive control method for converging the coefficients and tables of the distortion compensation control, first converging the coefficients of the predistorter 1, Next, the coefficients of the memory effect predistorter 2 are converged, and thereafter, an adaptive control method is alternately repeated. the

Example 6

An example of the simulation result of the sixth embodiment of the present invention will be described. the

FIG. 7( a ) shows an example of a simulation result when the predistorter 1 shown in FIG. 5( c ) is used without the memory effect predistorter 2 , assuming that there is no memory effect of the amplifier. 7( a ), ( b ), and ( c ), the horizontal axis represents frequency [MHz], and the vertical axis represents electric power spectral density [dB]. In the graph, the case without predistorter 1 ("no predistorter") and the circuit with only 3 orders of predistorter 1 ("O(3)"), and the circuit with 3 orders and 5 orders are represented The case of the circuit ("O(3,5)"), etc. the

FIG. 7( b ) shows an example of a simulation result when the predistorter 1 shown in FIG. 5( c ) is used, the memory effect predistorter 2 is not provided, and the memory effect of the amplifier is assumed. As observed from the graph, only about 5dB of distortion can be compensated due to the memory effect. the

FIG. 7(c) shows an example of a simulation result assuming a memory effect of an amplifier using the predistorter 1 shown in FIG. 5(c) and the memory effect predistorter 2 shown in FIG. 2 . For example, "O(3,5,7)E(2)" means 3 (O3), 5 (O5), and 7 (O7) passes of predistorter 1, and 7 passes (O7) of predistorter 2 are used In the case of 3 times (E2), the same applies to the others. As can be seen from the graph, the effect of the memory effect predistorter 2 can compensate distortion by 20 dB or more. As an example, if the predistorter 1 is used to 7 times (O(3,5,7)), and the memory effect predistorter 2 is used to 5 times (E(2,4)), then it can reach -60dB, ideal. the

Here, in the above-described embodiments, the nonlinear distortion component compensating unit is constituted according to the function of the predistorter 1 . the

As an example, in the above-mentioned structure shown in FIG. 5, the function of the quadratic power detector 71 and the function of the quadratic power detector 74 constitute an even power multiplication unit, and the function of the multiplier 72 and the function of the multiplier 75 An even power multiplication result multiplication unit is formed, the distortion compensation coefficient multiplication unit is formed by the function of the multiplier 73 or the multiplier 76, and the distortion compensation coefficient multiplication result addition unit is formed by the function of the adder 77. the

In addition, in the above embodiments, the memory effect distortion component compensating unit is constituted by the function of the memory effect predistorter 2 . the

As an example, in the above-mentioned structure shown in FIG. 2 , the function of the quadratic detector 11 and the function of the quadratic detector 16 constitute an even power multiplication unit, and the function of the delay circuit 12 and the function of the delay circuit 17 Constitute the delay unit of even power multiplication result, constitute the even power multiplication result time difference detection unit by the function of subtractor 13 and the function of subtractor 18, constitute the input signal multiplication unit by the function of multiplier 14 and the function of multiplier 19, pass The function of the multiplier 15 and the function of the multiplier 20 constitute a distortion compensation coefficient multiplication unit, and the function of the adder 21 constitutes a distortion compensation coefficient multiplication result addition unit. the

As another example, in the structures shown in above-mentioned FIG. 3 and above-mentioned FIG. The result delay unit constitutes the even power multiplication result time difference detection unit by the function of the subtractor 33,43, and constitutes the even power multiplication result time difference control value corresponding storage unit by the function of the comparison table (LUT) 34,44. In addition, in the above-mentioned FIG. 3 , the input signal changing unit (multiplication unit) is configured based on the function of the multiplier 35 . In addition, in the above-mentioned FIG. 4 , the function of the voltage variable attenuator 47 and the function of the voltage variable phase shifter 48 constitute input signal changing means (input signal amplitude phase changing means). the

The technical background related to the present invention is shown below. In addition, the items described here are not limited to all conventional technologies. the

For example, in a base station device of a mobile communication system using a wideband code division multiplexing (W-CDMA: wideband code division multiplexing) method as a mobile communication method, since it is necessary to make a wireless signal reach a physically distant mobile station device, Therefore, it is necessary to use an amplifier such as a power amplifier (PA) to greatly amplify signals such as multi-carriers. the

However, since an amplifier is an analog device, its input-output characteristics become a non-linear function. In particular, after the amplification critical called the saturation point, even if the electric power input to the amplifier increases, the output electric power is almost constant. Also, non-linear distortion occurs due to this non-linear output. The signal components outside the desired signal frequency band are suppressed to a low level by the band-rejection filter of the transmitted signal before amplification, but non-linear distortion occurs in the signal after passing through the amplifier, and the signal components are outside the desired signal frequency band (phase adjacent channel) leakage. the

For example, in a base station apparatus, since transmission electric power is high as described above, the magnitude of such leakage electric power to adjacent channels is strictly regulated, and how to reduce such adjacent channel leakage electric power becomes a big problem. Therefore, as one of the distortion compensation methods, there is a predistortion method, and in recent years, since amplification efficiency is emphasized, it has become the mainstream instead of the feedforward method. The predistortion method is a method of compensating the distortion of the output signal of the amplifier by providing in advance the inverse characteristics of AM-AM conversion and AM-PM conversion, which are nonlinear characteristics of the amplifier, to the input signal of the amplifier. the

FIG. 8 shows an example of the configuration of a functional block using an amplifier of the predistortion method, and an example of its operation. the

The input signal is input to the electric power detection unit 81, and the electric power or amplitude of the input signal is detected, and the detection result is associated as a reference variable of the distortion compensation table 82 composed of a memory or the like. In the distortion compensation table 82, a table for performing distortion compensation in a pre-distortion manner is stored. the

In the table of the distortion compensation table 82, the inverse characteristic of the nonlinear characteristic of the amplifier (amplification unit 84) to be compensated is reflected. Generally, AM-AM conversion (amplitude) using the electric power or amplitude of the input signal as an index is used. , AM-PM conversion (phase). The predistorter 83 controls the amplitude and phase of the input signal according to the reference result of the distortion compensation table 82 . The signal provided with distortion in advance by the predistortion method is amplified by the amplifying unit 84, and the output signal becomes a signal without distortion. The control unit 85 updates the distortion compensation table 85 according to the input signal and the output signal of the amplification unit 84 in order to adapt to the temperature changing environment. the

However, in the distortion generation mechanism of the amplifier, not only the AM-AM characteristics and AM-PM characteristics of instantaneous electric power, but also the fact that the current state changes according to the past state represented by the memory effect. In the conventional method, since the index used to refer to the distortion compensation table is only the instantaneous electric power, there is a problem that the nonlinear distortion caused by the memory effect cannot be compensated. the

Specifically, the memory effect acts as a hysteresis in AM-AM characteristics and AM-PM characteristics, and its influence generates unbalanced intermodulation distortion (IMD), which limits the performance of conventional predistorters based on instantaneous electric power of input signals. performance. For this reason, the conventional predistorter cannot generate accurate nonlinear inverse characteristics. the

Here, as an example of a method for solving the influence of the memory effect, consider a distortion compensation table having the current instantaneous electric power and the instantaneous electric power one unit time (for example, one sample) before as reference variables. the

FIG. 9 shows an example of a graph of a distortion compensation table in consideration of such a memory effect. The horizontal axis represents the instantaneous electric power, and the vertical axis represents the distortion compensation control value, representing the change per unit time. That is, the dimension of the instantaneous electric power before one unit time is added to the normal distortion compensation table. the

As an example, when the resolution of instantaneous electric power is 10 bits, 1024 tables (that is, 10 bits) are required for a conventional normal table. However, with such a configuration, although distortion can be compensated, the amount of storage becomes huge, and the creation of tables and learning for adapting to the environment are very difficult, so they are not practically available. the

In addition, in order to avoid these problems, a method of obtaining the differential coefficient at the previous time, referring to the correction table, and correcting the value of the conventional look-up table (LUT) is conceivable. However, in this method, even if the differential coefficient is the same, since the appropriate correction amount differs depending on the instantaneous electric power, an error is necessarily included in the correction table. For this reason, a disadvantage of reducing the amount of memory appears as deterioration of characteristics, and distortion cannot be fully compensated. the

Second, memory effects are specified in detail. the

FIG. 10 shows an example of a model of an amplifying unit in consideration of the influence of the memory effect (see, for example, Non-Patent Document 1). The distortion generated in this model cannot be compensated by the AM-AM characteristic and the inverse characteristic of the AM-PM characteristic which are the principle of predistortion. the

In addition, in this model, the entire structure shown in FIG. 10 above corresponds to the amplification unit, and since it is a model, each processing unit 91 to 96 does not necessarily exist in the amplification unit as it is. the

Amplifier 95 represents an amplifying part having only AM-AM characteristics and AM-PM characteristics, that is, an amplifying part that does not consider the memory effect, and represents a part that can completely compensate distortion by using the predistortion principle. the

Here, it is preferable that the power supply voltage of the electric power amplifier (PA) is constant, as described below, the memory effect occurs due to fluctuations in the power supply voltage. the

Generally, odd-order distortions appear near the carrier as IMD (IMD3, IMD5). the

On the other hand, the spectrum of the nonlinear even-order component has frequency components twice or more that of the baseband and input signals. Among them, a current having an even-order distortion component generated in the baseband flows into a drain bias circuit, and the current is converted into a voltage signal by a parasitic inductance in a bias circuit or an output matching circuit of a transistor (eg, FET). the

For example, when a wideband signal is used such as W-CDMA, since the frequency band of even-number distortion becomes higher, the voltage of even-number distortion increases, causing the drain bias to fluctuate. The carrier signal is re-modulated by this drain bias variation, and new distortion occurs near the carrier. the

When an amplifier affected by intermodulation distortion is modeled, it shows the so-called hysteresis characteristic in which multiple output voltages and phases appear for one input due to the memory effect of the inductor. the

Explanation will be given using the model shown in FIG. 10 above. the

The quadratic detector (quadratic circuit) 92 detects the quadratic distortion component of the input signal of the amplifier 95 generated in the baseband, and is assumed to be a current source in this model. the

The inductance 93 corresponds to a parasitic component included in the bias circuit and the output matching circuit of the amplifier 95 . For example, in the case of processing a wideband signal such as W-CDMA, the frequency bandwidth of the second-order distortion component of the baseband is wider than that of the baseband secondary distortion component. Since the inductor 93 has high impedance, a voltage is generated and the voltage of the bias circuit fluctuates. the

In addition, the input signal is subjected to a constant (fixed value) phase change in the fixed phase changer 91, and is remodulated according to the voltage change of the above-mentioned bias circuit. This remodulation is performed by multiplier 94 . Furthermore, the signal of the multiplication result of the multiplier 94 is added to the output signal from the conventional amplifier model (amplifier 95 ) by the adder 96 as a memory effect component. the

Thus, by amplitude-modulating the input signal with the voltage signal of the inductor 93, a new tertiary distortion is generated. Then, the signals from the two parts are combined by the adder 96 to generate an amplifier output signal including the influence of the memory effect. the

In addition, here, as an explanation of the generation mechanism of the memory effect, only the second-order distortion component is considered, but generally, even-numbered distortion components such as 4th order, 6th order, etc. are generated in the baseband, so offset components are also generated. In this case, the part corresponding to the quadratic detector 92 becomes the 4th power, the 6th power, etc., and is the same as the above-mentioned 2nd case, and the output from the part corresponding to the multiplier 94 is added to the output from the conventional on the output signal of the amplifier model (amplifier 95). This memory effect cannot be compensated in conventional predistorters that only use instantaneous electric power as a reference variable. the

Here, the configurations of the amplifier, amplifying device, transmitter, base station device, etc. with a predistortion system distortion compensation function of the present invention are not necessarily limited to the configurations shown above, and various configurations can be used. In addition, the present invention can provide, for example, a method or means for realizing the processing in the present invention, a program for realizing the method or means, a recording medium recording the program, and the like, and can also be provided as various devices and systems. the

In addition, the field of application of the present invention is not necessarily limited to the fields shown above, and the present invention can be applied to various fields. the

In addition, the present invention can be applied to various predistortion methods. the

For example, as a predistortion method, some frequency bands are baseband (BB), intermediate frequency (IF), or radio frequency (RF), and there are digital or analog processing. Although classified according to these treatments, it can be applied to any type. the

In addition, in the above-mentioned FIG. 1 and the above-mentioned FIG. 8, an example of the amplifier with the distortion compensation function of the pre-distortion method is shown, but it is not limited to this, and the required D/A can also be used according to the type of the method used. (D/A) converter, quadrature modulator (or quadrature modulation unit), up-converter, filter, etc. In addition, in the above-mentioned FIG. 1 and the above-mentioned FIG. 8, in order to adapt to environmental changes, there is no special limitation on the existence of the feedback signal transmitted from the amplification unit 3, 84 to the control unit 4, 85, etc., and may or may not be used. . In addition, in order to use such a feedback signal, a down converter, an oscillator, a filter, a quadrature demodulator (or a quadrature demodulation unit), an A/D (Analog/Digital) converter, etc. can be used. In addition, to detect distortion, an input signal can be used. the

In addition, as the various processes performed in the amplifier, amplifier, transmitter, base station, etc. with the distortion compensation function of the pre-distortion method of the present invention, it is possible to use, for example, hardware resources equipped with a processor and a memory through a processor. The control program is executed by executing a control program stored in ROM (Read Only Memory). In addition, for example, each functional unit for executing the processing may be configured as an independent hardware circuit. the

In addition, the present invention can also be realized as a computer-readable recording medium such as a floppy disk (Floppy: registered trademark) or a CD (Compact Disc)-ROM storing the above-mentioned control program, or the program (itself). The processing of the present invention can be realized by inputting this control program into a computer and executing it by a processor. the

Claims (6)

1. A kind of amplifier, this amplifier comprises the amplifying part that input signal is amplified and memory effect distortion component compensation unit, and this amplifier has pre-distortion mode distortion compensation function, it is characterized in that: In order to provide an inverse characteristic for compensating the distortion produced by the memory effect, the above-mentioned memory effect distortion component compensation unit modulates the amplitude and phase of the data signal from the predistorter with the time difference of the result of multiplying the input signal by an even power, thereby Compensate the distortion components caused by the memory effect of the amplifier, The memory effect distortion component compensation unit includes an even power multiplication unit that multiplies the input signal by an even power, an even power multiplication result delay unit that delays the signal of the even power multiplication result of the even power multiplication unit, and detects the even power The even power multiplication result time difference detection unit of the difference between the signal of the even power multiplication result of the multiplication unit and the delay signal of the even power multiplication result delay unit makes the signal of the detection result of the even power multiplication result time difference detection unit and the input signal an input signal multiplication unit for multiplication, a distortion compensation coefficient multiplication unit for multiplying a signal of a multiplication result of the input signal multiplication unit with a distortion compensation coefficient for compensating distortion, a distortion compensation coefficient multiplication unit for multiplying an input signal with a signal of a multiplication result of the distortion compensation coefficient multiplication unit Addition of distortion compensation coefficient multiplication result addition unit. 2. The amplifier of claim 1, wherein: Equipped with a nonlinear distortion component compensation unit to compensate the distortion components caused by the nonlinearity of the amplifier's AM-AM characteristics and AM-PM characteristics, The above-mentioned nonlinear distortion component compensation unit includes an even power multiplication unit that multiplies the input signal to an even power, and an even power multiplication result multiplication unit that multiplies the signal of the even power multiplication result of the even power multiplication unit with the input signal, A distortion compensation coefficient multiplication unit that multiplies a signal of a multiplication result of the even power multiplication result multiplication unit by a distortion compensation coefficient for compensating distortion, a distortion compensation that adds an input signal to a signal of a multiplication result of the distortion compensation coefficient multiplication unit Coefficient multiplication result addition unit. 3. The amplifier of claim 1, wherein: Equipped with a nonlinear distortion component compensation unit to compensate the distortion components caused by the nonlinearity of the amplifier's AM-AM characteristics and AM-PM characteristics, The above nonlinear distortion component compensation unit includes an envelope detection unit that detects the envelope voltage or envelope electric power of the input signal, and an envelope distortion compensation that stores the corresponding relationship between the envelope voltage or envelope electric power and the distortion compensation coefficient used to compensate the distortion A coefficient-corresponding storage unit, an input signal distortion compensation coefficient multiplication unit that multiplies the distortion compensation coefficient corresponding to the detection value of the envelope detection unit by the input signal according to the storage content of the envelope distortion compensation coefficient-corresponding storage unit. 4. The amplifier of claim 1, wherein: The memory effect distortion component compensation unit includes an even power multiplication unit that multiplies the input signal by an even power; an even power multiplication result delay unit that delays the signal of the even power multiplication result of the even power multiplication unit; The even power multiplication result time difference detection unit of the difference between the signal of the even power multiplication result of the multiplication unit and the delay signal of the even power multiplication result delay unit; store the value detected by the even power multiplication result time difference detection unit and be used for Distortion compensation for compensating distortion uses the even power multiplication result time difference control value corresponding storage unit of the correspondence relation of the complex number vector; The detection value corresponding to the distortion compensation complex vector for compensating the distortion, the input signal change unit that changes the input signal, The input signal changing unit is a multiplication unit that multiplies the input signal by a complex vector for distortion compensation for compensating distortion. 5. Amplifier according to claim 2 or 3, characterized in that: A control unit is provided for performing feedback processing and processing based on the level of the input signal for the distortion compensation processing performed by the nonlinear distortion component compensating unit and the distortion compensating process performed by the memory effect distortion component compensating unit. 6. Amplifier according to claim 2 or 3, characterized in that: A control unit is provided, after updating and converging the parameters of the distortion compensation processing of the nonlinear distortion component compensation unit, updating and converging the parameters of the distortion compensation processing of the memory effect distortion component compensation unit, and then alternately and repeatedly executing the update non-linear A process of converging the parameters of the distortion compensation processing of the linear distortion component compensating means, and a process of updating and converging the parameters of the distortion compensating process of the memory effect distortion component compensating means.

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